Electric switch



March 17, 1959 c. N. EHRLICH 2,878,336

ELECTRIC SWITCH Filed April 21, 1958 2 Sheets-Sheet 1 y/lllllz ylll B 9INVENTOR. CHARLES N. EHRLJCH ATTORNEY.

March 17, 1959 c. N. EHRLICH 2,878,336

ELECTRIC SWITCH Filed April 21, 1958 2 Sheets-Sheet 2 IOOQBS) o '1 22 64i as l' III III/Ill I v l i-25.44 IA'IA'JYIIAE'IIII 82 Sou- 92 noINVENTOR. CHARLES N. EHRLICH ATTORNEY.

United States Patent ELECTRIC SWITCH Charles N. Ehrlich, New York, N. Y.

Application April 21, 1958, Serial No. 729,917

Claims. (Cl. 200-865) This invention relates to electric switches, andmore particularly to switches of the type that are operated by theapplication of pressure to the sides thereof.

The desired result of this invention is to provide a switch that may beoperated by the application of pressure either by foot, hand, 'or anyother convenient means, to the sides of the body thereof to 'eifect amaintained electrical circuit after the removal of such pressure or toelfect a momentary electrical circuit that is continued for only as longas pressure is applied.

In carrying forth the purpose of the invention, it is an object thereofto provide a switch of the type that is operated by pressure but whichdistinguishes over prior known devices of the same kind in that it iscompletely enclosed and all spaces or openings are concealed from view,thereby presenting a desirable, decorative symmetrical appearance thatis appealing and pleasing to the eye, and wherein the structuralelements are protected from damage by preventing the entry of dirt orother foreign matter into the interior of the switch.

It is an object of the invention to provide a pressure operated switchthat incorporates the teaching of nonoverlapping yet relatively movablenormally spaced shell members that combine to form a composite housingwithin which the operating structure is enclosed and completelyconcealed by a novel encircling structure that se cures the member'stogether to limit their relative separation and to retain them inposition for hinged relative movement.

Another object of the invention is to provide a'switch that is easilyconstructed and the elemental details of which are uniquely arranged sothat it can be-assembled quickly and inexpensively by the use of novelpreassembled units mounted in but one of a plurality of members whichcomprise the switch housing.

It is another object of the invention to provide a switch that is sturdyin construction; one that will withstand the application of great forcesand pressures and one that is long-lasting since it comprises relativelyfew moving parts.

Another object of the invention is the provision of a novel actuatingstructure that includes a cam device which is caused to operate circuitclosing or opening electrical contacts in response to the relativemovements of the shell members of the composite housing in which thesame are enclosed.

Other and further objects of my invention reside in the structures andarrangements hereinafter more fully described with reference to theaccompanying drawings in which:

Fig. 1 is a perspective view of the electric switch constructed inaccordance with the teaching of the invention.

Fig. 2 is an exploded view of the elemental details of a switch thatwill provide a maintained electrical circuit.

Fig. 3 is a section of the side of the switch shown in Fig. 2 with thecontacts inopen circuit breaking position.

2,878,336 Patented Mar. 17, 1959 Fig. 4 is a view similar to Fig. 3wherein the housing and actuator structure are moved to an intermediatecontact closing position.

Fig. 5 shows the housing compressed closed and the electrical contactsin their closed position.

Fig. 6 shows the housing in its released normally open position and thecontacts in their maintained closed position.

Fig. 7 is a plan view of the lower shell member of the a housing.

Fig. 8 is a section taken of Fig. 7 along lines 8-8.

Fig. 9 is a section of Fig. 7 taken along lines 9-9.

Fig. 10 is a plan view of the upper shell member of the housing.

Fig. '11 is a side view of the shell member in Fig. 10.

Fig. 12 is a plan view of the strap.

Fig. 13 is a'section of Fig. 12'taken along lines 13-13.

Fig. 14 is a perspective view of the strap clip.

Fig. 15 is a perspective view of the actuator ratchet and cam.

Fig. 16 is a sectional side view of a momentary switch with the housingand contacts in their normally open separated position.

Fig. 17 is a sectional side view similar to Fig. 16 with the housingcompressed closed and the contacts in their engaged position, and

Fig. 18 is a perspective view of the actuator and contact member of themomentary switch.

Referring now to the drawings, Figs. 1 to 15 inclusive relate to theswitch for effecting a maintained electrical circuit and is generallyidentified by the numeral 20. Switch 26 comprises a plurality ofoppositely disposed upper and lower hollow bodies or shell members 22and 24. The members 22 and '24 are substantially alike in outerappearance andtherefore maybe said to have mirror-hand exteriors.

The upper and lower shells hingedly cooperate at'their rear portions todefine a composite housing wherein each shell member 22 and 24 isprovided with an encompassing shelf 26 extending laterally from theexterior of the body. The shelf is symmetrical on the opposite sides ofeach shell member and tapers upwardly from the front toward the rear endthereof wherein it is widest. A pair of spaced locating or positioningpins 28 project upwardly from the face at the rear portion'of the lowershell member 24 for cooperating joining engagement with a similarlyspaced pair of recesses 30 that are provided in the face of therear'portion of the upper shell member 22.

The positioning means 28 and 30 serve to locate the rear portions oftheir respective members for hinged relative movement thereabout. Inorder to aid in this hinged relative movement, the upper shell .memberis tapered at 32 (Fig. 11) along its wire receiving extension 34, whilethe wire receiving extension 36 of the lower shell member24 remainssubstantially planar.

Both the upper and lower shell members may be compression molded ofnon-conductive phenolic or other insulating material. The lower shellmember 24 is provided with a separator 38 that is molded integral withand projects upwardly from the base of the interior thereof. It extendslongitudinally forward beginning at the rear of the member from the wirereceiving extension 36 so as to provide an insulator between'the twoseparated contact units to be described.

Located at the forward end of the separator'38, is a groove 40 whichextends from a side wall of the interior of the member 24 tosubstantially the midpoint of the width of the hollow interior of suchmember. A longitudinally extending groove 42 slopes upwardly from theundercut 40 to the base surface of the interior of the member and islocated on one side of the midpoint of the merals 94 and 96 (Fig. 2).termed the lower contact unit while the unit 96 may be width of thehollow interior of the member 24. Equally spaced on opposite sides ofthe longitudinal center line of the member 24 and projecting upwardlyfrom the base of the interior of the member to form a guide openingtherebetween are a pair of spaced guides 44 and 46.

The forward ends of the guides 44 and 46 terminate at pivotal mountingblocks 48 and 50 respectively. The mounting blocks 48 and 50 are similarin detail in that each of them includes a pivot mounting slot 52 thathas a surface 54 preferably tapered at its forward end. The guides 44and'46 each have their lateral outer surfaces 56 .and 58 arrangedsubstantially parallel with the adjacent interior rearwardly taperedside walls 60 of the lower shell member 24, as are also the side walls62 of the separator 38, for a purpose to be described.

, The upper and lower shell members 22 and 24 are oppositely positionedfor coincident relative movement at their rear portions by thecoinciding cooperation of the locating pins 28 and the correspondingrecesses 30. The

. tapered surface 32 defined on the wire receiving extension 34 of theupper shell member 22, enables the members to move smoothly along theirrear portions without obstruction.

The shell members 22 and 24 are normally urged into spaced relationshipto assume the relative position as shown in Figs. 1, 3 and 6 by anactuating structure 63 (Fig. 2) interposed within the housing. Theactuating structure 63 comprises a yieldable means in the form of a coilspring 64 that has its ends 66 and 68 bent normally perpendicular to theplane of the coils 70. The leg 66 is adapted to be pivotally seated inthe groove 40 defined in the interior of the lower shell 24 and retainedtherein against removal in a manner to be described. The arm 72 taperingupwardly from the bent end 66, is adapted to fit and swing within thesloped groove 42 that coincides with the end of the groove 40. Hence,one end of the coil spring 64 is adapted to be pivotally butnon-removably'mounted within the lower shell member 24.

The other end 68 of the coil spring 64 is secured in a slidable pawl 74that is provided with a struck portion 76 within which the free springend 68 is received to secure the pawl and spring together. The pawl 74is mounted between the upwardly projecting laterally spaced guides 44and 46 for guided sliding movement therebetween. The parallel innerfacing sides of the guides 44 and 46 7 thus prevent sideward movement ofthe pawl and direct the same for forward or rearward movement within theslot therebetween in response to the yielding movement of the free leg68 of the spring 64.

Rotatably mounted in the pivot mounting slots 52 of the mounting blocks48 and 50 respectively, is a ratchet device 78 having a pair of pivots80 extending from the ends thereof. The ratchet 78 is included in theactuating structure 63 which comprises also the yieldable means 64 andthe actuating pawl 74. A cam 82 is fixed to the ratchet to rotatetherewith and, in the instant embodiment, is formed as an integral partthereof. The cam is elongated in opposite directions to provide a pairof radially opposed cam surfaces 84 and 86.

The ratchet device 78 is provided with four fiat or planar faces 88 ofwhich terminate in a ratchet tooth or jutting lip 90 adapted forengagement with a bent forward end 92 of the pawl 74. The forward end 92of the pawl 74 is bent slightly upward for successive engagement withthe teeth 90 of the ratchet to rotate the ratchet and the cam that isfixed thereto. The manner of engagement of the forward end 92 of thepawl with the teeth or jutting lips 90 of the ratchet device 78, isshown more clearly in Figs. 3, 4, 5, and 6, to be described presenfly.

The switch 20 comprises a plurality of preassembled electrical contactunits generally identified by the nu- The contact unit 94 may be termedthe upper. Each contact unit 94 and 96 is substantially alike in thatthey comprise lower and upper spring contact members or elements 98 and100 respectively. Included in each contact unit is a securing orfastening bracket 102. The brackets 102 of each unit are of mirror-handconstruction; hence, the description of one should sufiice for both.

The bracket 102 has a forwardly extending leg 104 that terminates in alocking point 106. The brackets 102 may be of spring-tempered materialand are provided with a widening surface 108. The opposite end of eachbracket terminates in a locking point 110, While interposed between thepoint and theabutment 108 is an inverted V-shaped yieldable forceapplying formation 112 that is provided with a threaded opening 114 onits rearward surface.

The lower contact member 98 is substantially planar, terminating in alaterally offset leg 116 having secured thereto an electrical silvercontact element 118. The opposite end of the lower contact member 98 isbent downwardly at its rear so that the same may mate with the rearsurface of the inverted V-shaped formation 112 of the bracket 102 to bemade unitary therewith, as by spotwelding or soldering. A screw 120,passing through a suitable opening 122 provided in the contact elementand threadedly engaging with the threads 114 of the bracket, provides amechanical means to fasten the electrical line or cord to the contactelement 98. The upper contact unit 96, comprising the spring contactmember 100, is similarly preassembled.

To insure a proper overlapping arrangement of the spring contact members98 and 108, the upper spring contact member 100 is provided with a leg126 that is bent upward normal to the plane of the spring contactmember. The end 128 of the leg 126 is then again bent laterally intooverlapping relationship with the offset leg 116 of the lower springcontact member 98. A silver contact element 130 is suitably securedthereto for electrical circuit engagement with the lower contact element118 on the member 98.

Hence, it will be recognized by those skilled in the art, that thecontact units 94 and 96 may be preassembled in production operationsprior to their assembly in shell 24. Each contact unit is locked inposition in the lower shell member 24 after the actuating mechanism 63has been assembled into the same shell member, by causing the oppositelypointed locking ends 106 and 110 of the brackets 102 to piercinglyengage the molded material of the shell member.

With the actuating structure 63 mounted in position in the lower shell24, as previously described, the lower contact unit is forcibly pressedinto the lower shell member. This causes the inverted V-shaped formationof the bracket of the lower contact unit to squeeze togetherautomatically to move the pointed ends 106 and 110 closer together. Theforward narrow leg 104 of the bracket of the unit 94 is inserted in thespace between the parallel tapered walls of the guide 46 and thecorresponding side wall 60 of the lower shell member. Its widened bodyportion immediately beyond the abutment 108 will overlap the end 66 ofthe spring 64 seated within the groove 40, while the rear pointed end110 thereof will be situated between the wall 62 of the separator 38 andthe corresponding parallel tapered wall 60 of the shell member.

The V-formation exerts a force to expand the bracket back to its normallength. The expansion causes the pointed forward end 106' to dig intothe block 48 while the rear pointed end 110 simultaneously digs into therear wall of the shell member. The bracket 102 is thus locked securelyin position at its forward end tov the block 48, prevented from sidewardmovement by ongaging along its leg 104 between the tapered walls of theguides 46 and 60, against sideward movement at its rear by the taperedwall 62 of the separator 38 and the corresponding wall 60 of the shellmember.

At the same time, the bottornmost surface of the bracket will seatagainst the base of the shell to retain the end 66 of the spring 64 inthe groove 40. The forward end 116 of the contact member 98 is soarranged as to constantly bear against and apply a pressure to theratchet device 78 pivotally mounted in the slots 52 of the blocks 48 and50 to retain the same therein, thereby insuring that the ratchet devicewill not be dislodged from its pivot seat. This normal arrangement ofelemental details is more clearly shown in Fig. 6.

The upper contact unit 96 is similarly secured in position between theguide block 44 and its corresponding wall 69) of the shell member, andalso between the wall 62 of the separator 38 and the same shell wall 60,in the manner described with respect to the lower contact unit 94except, however, that the ofiset leg 128 of the upper spring contactmember 100, will be in overlying relationship and biased into constantyieldable engagement with the contact element 118 of the lower contactmember 98.

It will be noted that the coils 70 of the spring 64 project upwardthrough the lateral spacing between the contact elements 98 and 100 ofthe two units for engagement with the inner surface of the upper shellmember 22. Its two perpendicularly disposed legs 66 and 68 maintain thecoils 70 upright to constantly apply a pressure to urge the forwardportion of the upper shell member into normal separation and spacedrelationship with the forward portion of the lower shell member. Thisnormal clam-like spaced relationship of the shell members is shown inFigs. 3 and 6 and, thus, under usual conditions, would permit the entryof dirt or other foreign matter into the interior of the switch to causedamage to the elemental details thereof. Moreover, the separation alsopresents an ugly, unsightly appearance.

To eliminate the entry of dirt, to fully conceal the interior from view,to secure the shell members together for hinged relative movement, andto limit their separation, there is provided a strap constructiongenerally identified by the numeral 131. The strap construction 131comprises a channel-shaped member 132 having a body 133 and legs 134.The body 133 is shaped in the form of a -C to completely encircle bothshell members 22 and 24 and to engage with the shelves 26 thereof. Thestrap 132 encompasses the full periphery of the shells by engaging withthe shelves thereof and terminating at the rear relatively movableportions of the members 22 and 24 adjacent the wire receiving extensions34 and 36 thereof. The ends of the strap body terminate inperpendicularly disposed relatively spaced fingers 136 and 138 that areadapted to fit into'a slotshaped elongated aperture 140 of a resilientchannelshaped enclosing clip 142.

With the body strap 132 completely encircling the shells 22 and 24 andengaging the shelves 26 thereof, the terminating fingers 136 and 138will abut against the opposite side of the lateral walls of the wirereceiving extensions 34 and 36. The clip 142 is then-moved over theextensions 34 and 36 to accommodate the same in its aperture 140, alongwith the projecting fingers 136 and 138. Being resilient, the clip 140will yield at its upper and lower ends 144 to flex over and about theleg portions 134 of the body 132 adjacent its fingers 136 and 138 tocomplete the strap construction and secure the same to the shelves 26.Although the ends 144 may" be assembled over the legs 134 by hand, theycannot be removed from engagement therewith without the use of a toolthat will fit beneath the ends to ilex them oil the legs.

Thus, the strap construction 131 serves to secure the shells 22 and 24together for their hinged relative movement about their rear portionslocated by the cooperating pins 28 and recesses 30. It serves to securethe two shell members together to form the composite switch housing andto limit their relative spacing which results from the normal urging ofthe yieldable means 64. It also completely encloses any openings orspaces between the shell members to conceal the internal constructionthereof from View, rendering the interior invisible and resulting in anunusually decorative appearance. The tapered rear end 32 of the uppershell 22 remains in surface engagement with the corresponding portion ofthe lower shell 24 when the two shells are in their normally openposition while the tapered shelves 26 permit the hinged movement attheir narrowed forward end, but remaining in hinged contact with thestrap 131 at their widest rear ends.

The operation of the instant invention is clearly shown in Figs. '3 to 6inclusive wherein Fig. 6 shows the ar rangement of detailed elements intheir normal relationship. The shells 22 and 24 of the switch housingare normally urged spaced apart at their forward ends by the yieldingspring means 64, while their spacing is limited by the encompassingstrap construction 131 that has its legs 134 in complete peripheralencircling engagement with the shelves 26. The strap construction thuscompletely seals and conceals the interior of the switch and the spacebetween the shell members.

A two-wire line or cord 144 (Fig. l) entering the switch 20 at the rearthereof, is secured between the wire receiving extensions 34 and 36 ofthe strapped shell members. One of the two wires of the line 144 willserve as an electrical conductor for the upper contact unit 96, whilethe other wire will form the conductor for the lower contact unit 4.This is accomplished by winding the stripped end of each one of thelines of the wire 144 about the threads of a screw after the screw headshave been backed off of the inclined legs of their respective contactmembers. With the stripped end of the wire securely wrapped about thethreads of their respective screws, the screws are again threadedtightly into their brackets.

Under normal conditions, the spring contact members 98 and 100 arebiased into circuit engagement, with the lower contact memberresiliently bearing upon a flat surface 88 of the ratchet device 78 tomaintain the same in the pivot slots 52. Hence, under normal conditions,a circuit is closed across the two lines of the wire 144 by way of theengaging contact elements 118 and of the lower and upper contact units94 and 96 respectively. When in this normal position, the actuator 74 iswithdrawn away from the ratchet tooth or jutting lip 90 of the ratchetdevice while the spring 64 has its perpendicularly disposed legs 66 and68 in normal closed relationship.

In order to release the maintained circuit of the normally closed lowerand upper contact units 94 and 96, the shell members 22 and 24 arecompressed toward each other by the simple application of pressureapplied to their outer surfaces 146 (Figs. 1 and 2). The appliedpressure only need be of sufficient force to overcome the normal urgingof the spring 64 serving to separate the shells. As the shells are movedtoward each other by the application of pressure, they pass through theinter mediate closing position shown in Fig. 4, causing the spring coilsto contract, to correspondingly displace the movable leg 68 forwardlyalong the base of the lower shell member between the guides 44 and 46.

Accordingly, the pawl slide 74 is displaced with its connecteddisplaceable leg 68 of the spring 64. The upwardly bent forward end 92of the sliding pawl 74 is thus moved into engagement with the facingjutting lip 90 of the ratchet device 78 to progressively engagetherewith as the shell members are moved closed toward each other and asthe spring 64 is compressed and the legs thereof moved further apart inresponse to the relative closing movement of the shells.

Continued closing movement of the shells will thereby serve to operatethe actuator structure 63 until the 7 pawl rotatably actuates theratchet device 78 to present a new flat face 88 to the undersurface ofthe lower contact member 98 that bears thereagainst. The rotativemovement of the ratchet device accordingly serves to rotate the cam 82that is predeterminately positioned thereon and designed to move intoengagement with the undersurface of the forward portion of the upper contact member 100 to forcefully and positively lift the same out ofengagement with the lower contact member 98.

It will be recognized that each time the shell members 22 and 24 arecompressed together to close the space therebetween at their forwardends, the actuating mechanism 63 will operate in response thereto torotate the ratchet device 78 one-quarter turn. Because the cam surfaces84 and 86 are arranged in alignment with alternate ratchet surfaces 88,each quarter turn of the ratchet will cause the contact members 98 and100 to move into or out of closing circuit engagement alternately inresponse to sucessive closing movements of the shell members of thehousing.

Assuming that the structural details of the maintained switch 20 areoriginally in the relative positions as shown in Fig. 6, the actuatingstructure will operate in response to a closing movement of the shellmembers 22 and 24, to cause the rotation of the ratchet and cam 82. Asthe cam is rotated from its inactive position in Fig. 6 toward itsactive position in Fig. 3, it will engage with the undersurface' of theupper contact member 100, separating the same from the lower contactmember to open the circuit therebetween. When pressure on the shells isrelaxed, the legs of the spring 64 will again move back to their normalposition and the shells will be expanded and spaced from each other toassume the position shown in Fig. 3 in response to the normal urging ofthe spring.

With the contacts open as shown in Fig. 3, a further successivecompression of the shells will cause the actuator mechanism 63 to assumethe intermediate position as shown in Fig. 4. Fig. 4 shows the contactdisengaging cam surface partially moved out of engagement with the uppercontact member 100. Continued compression of the shells toward eachother will cause them to assume the closed position as shown in Fig.wherein the disengaging cam surface is moved fully out of engagementwith the contact 100 and is substantially perpendicular to the uppercontact member. The contact member is thus permitted to resume itsnormally closed circuit engaging position with the lower contact member98. Relaxation of pressure on the shells automatically will permit themto resume their normally spaced relationship in response to the normalurging of the spring 64.

A momentary circuit may be effected for the duration of the compressedclosed relationship of the shell members 22 and 24 simply by revisingthe previously described structure in a manner to be described.

Referring now to Figs. 16, 17, and 18, it will be noted that thestructural details of the switch generally identified 149 are basicallythe same as those described with respect to the switch 20. It differstherefrom only in the provision of an inclined finger 150 that isprovided on the lower contact member 98 of the lower contact unit 94.The inclined surface 150 is adapted to be engaged and caused to moveupwardly by the operation of an actuator slide 152 more clearly shown inFig. 18. The slide 152 is substituted for the pawl 74 of the previouslydescribed maintained switch.

The displaceable end 68 of the spring 64 is secured to the slide 152 ina notched opening 154 defined between an abutment 156 and cam means 158.adapted to be guided for sliding movement between the guide blocks 44and 46in the same manner as in the pawl 74. The cam means 158 isprovided with an actuating cam surface 160 that is inclined forcomplementary engagement with the inclined surface 150 provided on thelower contact member 98. The sliding displacement Slide 152 is of theactuator slide 152, in response to the displacement of the spring end 68in accordance with and in response to the closing and opening hingedmovements of the shells 22 and 24, is accomplished much in the samemanner as the pawl 74 previously described.

However, in'the instantaneous or momentary switch shown in Figs. 16 to18, the lower and upper spring contact members 98 and are normallybiased apart into spaced relationship rather than into contact circuitengaging relationship as in the maintained switch 20 previouslydescribed. Hence, to close a circuit across the contact members 98 and100 in the instant embodiment 149, it is necessary to physically andpositively move the contact members into engagement. This engagement iseffected each time that the shell members 22 and 24 are hingedly movedcloser toward each other to assume the position as shown in Fig. 17.

As the shells are compressed closed, the movable leg 68 of the spring isdisplaced, moving the slide 152 with it. The forward cam surface 160 isprogressively moved toward and into complementary engagement with theinclined surface of the lower contact member 98. Continued forwarddisplacement of the slide will positively lift the contact member 98 tocause the same to move into engagement with the upper contact member 100until its topmost cam surface 162 is in seating engagement with theunderside of the lower contact member 98. This seating engagement willretain the contact member 98 in circuit closing engagement with theupper contact member 100 for as long as the shells 22 and 24 arecompressed into their closed relationship as shown in Fig. 17.

Relaxation of pressure on the shells thus allows the normal forceapplied by the yieldable means 64 to again automatically urge the shellsinto their spaced separated relationship as shown in Fig. 16. Themovement of the spring 64 toward its normal position retracts anddisplaces its movable end 68 closer to the immovable end 66 to move withit the slide 152. As the slide is moved away from and out of engagementwith the undersurface of the lower contact member 98 and progressivelyout of camming engagement with the inclined surface 150, the lowercontact member is caused automatically to resume its open position withrespect to the upper contact member 100.

While there have been shown and described and pointed out thefundamental novel features of the invention as applied to severalpreferred embodiments thereof, it will be understood that variousomissions and substitutions and changes in the form and details of thedevices illustrated and in their operations may be made by those skilledin the art, without departing from the spirit of the invention. It isthe intention, therefore, to be limited only as indicated by the scopeof the claims appended hereto.

I claim:

1. An electric switch comprising oppositely disposed normally spacedmembers joined about a portion thereof for relative movement, strapmeans enclosing the space between said members and joining the sametogether at said portion for said relative movement, electrical contactmeans between said members to open or close a circuit, and actuatormeans including means normally spacing said members and responsive totheir relative movement to open or close said contact means.

2. An electric switch comprising a pair of shells coacting for hingedopening or closing relative movement, electric contact means betweensaid shells engageable to close a circuit therebetween, actuator meansto urge said shells to a normally open-sided relationship and responsiveto the relative movements of said shells to cause said contact means toassume open or closed positions, and means engaging said shells to fullyenclose the normally open sides thereof and retain the same together forsaid coacting hinged relative movement.

3. In an electric switch, a housing defined by upper and loweroppositely disposed members of mirror-hand exteriors, said members eachhaving a bodyandan encompassing shelf' extending from theexterior ofsaid body, said shelf being symmetrical on the opposite sides o'fleacho'f'said bodies and tapering upwardly from the front end towardthe rearend thereof, said members being normallyspaced from each other at theirfront ends and coacting attheir rear ends for hinged relative movement,strap -means encircling "said members and engageable with saidshelves toretain the members together for said coactinghing'ed relative movementand to conceal the space therebetween.

4. In a switch as in claim 3, a pair of electrical contact meansfastened in said lower member for circuit engagement, and actuator meansresponsive to the closing movement of said members to cause said contactmeans to move into or out of circuit engagement and including meansyieldable to constantly urge said members into said normally spacedrelationship.

5. In a switch as in claim 3, said strap means being in the form of achannel having a substantially C-shaped body terminating at therespective ends thereof in perpendicularly disposed relatively spacedfingers and including a channel-shaped resilient clip having an openingtherein to receive said fingers and secure said strap about saidshelves.

6. An electric switch comprising a housing having upper and lower shellshingedly movable at one of their ends and normally spaced from eachother at the other of their ends, strap means encircling said shells toseal said space therebetween and engageable therewith to retain the sametogether for said hinged movement, contact means in said housing,actuator means to cause said contact means to move between open andclosed positions, said actuator means including means yieldably urgingsaid shells into said spaced relationship and responsive to the movementthereof to operate said actuator means.

7. An electric switch as in claim 6, means to fasten said contact meansin said lower shell, said actuator means being mounted in said lowershell and including means engageable with said contact means to causethe same to move between open and closed positions alternately inresponse to successive shell closing movements.

8. An electric switch as in claim 6, means to fasten said contact meansin said lower shell, said actuator means being mounted in said lowershell and including means engageable with said contact means to closethe same in response to the closing movement of said shells.

9. An electric switch comprising a housing including oppositely disposednormally spaced members hingedly moved closed in response to pressureapplied thereto, strap means encircling said members and engageabletherewith to conceal the space therebetween and to retain the sametogether for said hinged movement, electrical contacts in said housing,an actuator in said housing to cause said contacts to move betweenclosed and open positions, and spring means included in said actuatorand having a normal position to constantly urge said members into theirnormal spaced relationship and displaceable by the closing of saidmembers to operate said actuator.

10. A switch as in claim 9, wherein said actuator comprises a ratchetrotatably mounted in one of said members and having predeterminatelyarranged cam means engageable with a' certain one of said contacts toopen the same or permit the same to close alternately in response tosuccessive closing movements of said members, and pawl means connectedwith said spring means and responsive to the displacement thereof tosuccessively engage said ratchet to rotate the same and said cam means.

11. An electric switch as in claim 9, said actuator comprising a slideconnected with said spring means and having cam means thereon engageablewith a certain one of said contacts to close said contacts in responseto the displacement of said spring means.

12. An electric switch comprising a housing including normallyspacedupper and lower relatively movable members, means urging said membersinto spaced relationship and displaceable in said housing in response totheir relative movement, means encircling said housing and coacting withsaid members to limit the space therebetween, upper and lower contactmembers, and actuating means including said urging means to cause theoperation of said contact members between open and closed positions inresponse to the displacement of said urging means.

13. An electric switch as in claim 12, said urging means being a coilspring having anend thereof immovably mounted in said lower housingmember and the other end'thereof being connected with said actuatingmeans, and its coil being engageable with said upper housing member.

14. An electric switch as in claim 13, upper and lower preassembledcontact units, said units each including a bracket having means tofasten the same to said lower housing member and means cooperable withsaid bracket to secure a respective one of said contact members thereto.

15. A momentary switch comprising upper and lower normally spacedrelatively movable shells each having a shelf, cooperating positioningmeans on each of said shells, strap means engaging said shelves to limitthe separation of said shells and concealing the space therebetween, acam slide longitudinally displaceable in said lower shell and having acam face, a coil spring connected at its one end with said slide andseated on said lower shell at the other end thereof, the coils of saidspring applying a force to said upper shell normally to space the samefrom said lower shell, normally open upper and lower contact units eachincluding a contact member, a bracket secured to each of said contactmembers, one of said brackets immovably securing said other end of saidcoil to said lower shell, means on said brackets to secure itsrespective contact unit to said lower shell, and one of said contactmembers having a cam face engageable with said cam face of the cam slidewhereby relative closing movement of said shells will close said contactmembers and spacing movement of said shells will permit said contactmembers to open.

16. A maintained switch comprising upper and lower normally spacedrelatively movable shells each having cooperating positioning means,strap means engaging said shells to limit the separation thereof and toconceal the space therebetween, upper and lower contact units eachincluding a contact member, a bracket, each bracket being secured to itsrespective contact member, said contact units each being secured in oneof said shells by their respective brackets, a coil spring between saidcontact units having one of its legs immovably secured to said one shellby one of said brackets and its coils applying a force on the other ofsaid shells to space the shells from each other, rotatable cam meansmounted in said one shell and adapted to engage said contact members toopen the same and to permit the same to close alternately in response tosuccessive space closing movements of said shells, and means betweensaid cam means and the other leg of said spring to rotate said cam meansin response to the space closing movements of said shells.

17. A switch comprising upper and lower normally spaced shells arrangedfor hinged relative movement, strap means engaging said shells to limittheir separation and to conceal the space therebetween, upper and lowercontact units each including a contact member, a bracket included ineach of said units and having means to secure its respective unit to oneof said shells yieldable means immovably secured to said one shell byone of said brackets and constantly urging the other of said shells awayfrom said one shell, cam means mounted on said one shell and movable tocause the movement of said contact members between open and closedpositions, said yieldable means having displacing movement in responseto the relative movement of said shells, and means connected to saidyieldable means to move said cam means in response to the displacingmovement thereof.

18. A switch comprising a composite housing defined by'oppositelydisposed normally spaced shells of mirrorhand exterior having hingedrelative movement, means encircling said shells to limit and conceal thespace therebetween and to retain the same together for said hingedrelative movement, operable cam means, a plurality of contact membersmovable between open and closed positions in response to the operationof said cam means, and means yieldingly urging said shells into theirnormally spaced relationship and movable in response to their hingedrelative movement to operate said cam means.

f2 19. A switch as in claim 18, rotatable ratchet means to operate saidcam, and pawl means connected with said yielding means for movementtherewith to rotate said References Cited in the file of this patentUNITED STATES PATENTS 1,003,391 2,234,876 Rehrer Mar. 11, 1941 2,812,402

Dixon Nov. 5, 1957 Barber et a1. Sept. 12, 1911 I

